[AGP 9] Update Warn Version to AGP 9+

[jesswrd]

Raised warn version to AGP 9.0.1 and error version to right before AGP 9 for upcoming stable release. This way, most Flutter Android developers will upgrade their AGP version to 9.0.1, which means they will start seeing the Built-in Kotlin migration warnings.

Since I intend on CP-ing this to beta, this PR contains the minimum required changes to raise the warn version to AGP 9.0.1 and the error version to 9.0.1. As in I changed packages/flutter_tools/gradle/src/main/kotlin/DependencyVersionChecker.kt and a lot of presubmits failed. All other changes had to be made in order to pass presubmits. The following test projects (or tests with projects) had minimal dependency upgrades in a while, so tests failed because they fell below the error version:

• flutter/dev/integration_tests/module_host_with_custom_build_v2_embedding
• flutter/dev/integration_tests/pure_android_host_apps/android_custom_host_app
• flutter/packages/flutter_tools/test/integration.shard/test_data/deferred_components_project.dart
• flutter/packages/flutter_tools/test/integration.shard/android_gradle_legacy_flutter_plugins_strings_in_comments_test.dart
• flutter/dev/devicelab/bin/tasks/android_java17_dependency_smoke_tests.dart
• flutter/packages/flutter_tools/test/android_java17_integration.shard/android_dependency_version.dart

In this PR, I upgraded those dependency versions to the error version (the minimum change required). In a future PR (issue here), I will align those project dependency versions with the current template versions (or at least a safer/modern version between the warn version and template version).

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the AI contribution guidelines and understand my responsibilities, or I am not using AI tools.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• I followed the breaking change policy and added Data Driven Fixes where supported.
• All existing and new tests are passing.

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Code Review

This pull request updates the supported, warning, and error thresholds for Gradle, Android Gradle Plugin (AGP), and Kotlin Gradle Plugin (KGP) versions, and updates integration tests and version checks accordingly. Feedback on the tests recommends avoiding boundary values that are exactly equal to the error or warning thresholds to prevent fragile test cases and ensure robustness against future comparison logic changes.